还是20楼的公式, 从62开始就对不上了。
x+y+z+u+v+m=N的解组数,限制条件未知数取数不能取7的倍数
N是7的倍数余数是0,LinearRecurrence[{6, -15, 20, -15, 6, -1}, 15]
{-1197, -6, 0, 6, 1197, 11424, 51870, 163716, 414807, 906318, 1779420, 3221946, 5475057, 8839908}
N是7的倍数余数是1,LinearRecurrence[{6, -15, 20, -15, 6, -1}, 15]
{-762, -1, 0, 21, 1792, 14658, 62244, 189120, 467466, 1003737, 1945328, 3487239, 5878740, 9430036}
N是7的倍数余数是2,LinearRecurrence[{6, -15, 20, -15, 6, -1}, 15]
{-456, 0, 0, 56, 2583, 18564, 74215, 217650, 525546, 1109808, 2124234, 3771180, 6308225, 10054836}
N是7的倍数余数是3,LinearRecurrence[{6, -15, 20, -15, 6, -1}, 15]
{-252, 0, 0, 126, 3612, 23213, 87870, 249375, 589036,1224342, 2315628, 4072740, 6761700, 10711371}
N是7的倍数余数是4,LinearRecurrence[{6, -15, 20, -15, 6, -1}, 15]
{-126, 0, 0, 252, 4943, 28734, 103425, 284620,658392,1347948, 2520294, 4392900, 7240365, 11401082}
N是7的倍数余数是5,LinearRecurrence[{6, -15, 20, -15, 6, -1}, 15]
{-56, 0, 0, 456, 6642, 35259, 121100, 323715, 734076,1481242, 2739024, 4732650, 7745430, 12125421}
N是7的倍数余数是6,LinearRecurrence[{6, -15, 20, -15, 6, -1}, 15]
{-21, 0, 1, 762, 8778,42924, 141120, 366996, 816557, 1624848, 2972619, 5092990, 8278116, 12885852}
58 2124234
59 2315628
60 2520294
61 2739024
62 2972613
63 3221910
64 3487113
65 3770844
66 4071984
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